Lattice softening in body-centered-cubic lithium-magnesium alloys
Lattice softening in body-centered-cubic lithium-magnesium alloys
复制标题
体心立方锂镁合金中的晶格软化
DOI：
10.1103/physrevmaterials.1.033606
复制
发表时间：
2017
影响因子：
3.4
通讯作者：
T. Tsuru and D. C. Chrzan
中科院分区：
文献类型：
--
作者：
I. S. Winter;T. Tsuru and D. C. Chrzan
用第一性原理研究了体心立方(Bcc)/六方密排(Hcp)过渡相附近晶格软化对锂镁合金的影响。结果表明，当锂镁合金成分接近体心立方相的稳定极限时，合金的剪切模软化，声学声子在高对称点和高对称点之间分支。这种软化伴随着位错核心区尺寸的增大。理想的抗拉强度计算表明，锂镁合金的有序相本质上是脆性的。讨论了使合金更具韧性的方法，并对这些合金表现出树胶-金属行为的倾向进行了评估。
A first-principles investigation of the influence of lattice softening on lithium-magnesium alloys near the body-centered-cubic (bcc)/hexagonal close-packed (hcp) transition composition is presented. Results show that lithium-magnesium alloys display a softening of the shear modulus, and an acoustic phonon branch between theandhigh symmetry points, as the composition approaches the stability limit for the bcc phase. This softening is accompanied by an increase in the size of the dislocation core region. Ideal tensile strength calculations predict that ordered phases of lithium-magnesium alloys are intrinsically brittle. Methods to make the alloys more ductile are discussed, and the propensity for these alloys to display gum-metal-like behavior is assessed.